Batch sparging is so wonderfully easy. 83% every time on a double batch sparge.

What do you get with only one sparge? I get 83-85% with one.

I don't know how you do it. I get around 74% with my mill set at .035".

The first couple times I batch sparged, I was getting around 68% efficiency. I was also using really small hosing to drain my mash tun - it was taking ~15min! I changed out my hosing to 1/2", drain in 3 min and am now getting ~83% efficiency. Not sure why this worked but I've never looked back.